## Program to determine whether a given number is a twisted prime number

A number is called a twisted prime number if it is a prime number and reverse of this number is also a prime number.

Examples: 2, 3, 5, 7, 11, 13, 17, 31, 37, 71, 73, 79

The algorithm to check whether a given number is a twisted prime number is given below.

### Algorithm

• STEP 1: START
• STEP 2: DEFINE n, reverse, flag
• STEP 3: SET sum = 0
• STEP 4: ENTER n
• STEP 5: REPEAT STEP 6 to 8 UNTIL (n!=0)
• STEP 6: reverse = n%10
• STEP 7: sum = sum*10 + reverse
• STEP 8: n = n/10
• STEP 9: SET flag =0
• STEP 10: REPEAT STEP 11 UNTIL j<=sum/2
• STEP 11: if(sum%j)==0
then
set flag = 1
break
• STEP 12: if(flag==0)
then PRINT "yes"
else
PRINT "no"
• STEP 13: END

### Java Program

Output:

```Enter the prime number?
43
Not Twisted Prime
```

### Python Program

Output:

```Enter the prime number?
13
Twisted Prime
```

### C Program

Output:

```Enter the prime number?
11
Twisted Prime
```

### C# program

Output:

```            Enter the prime number?
13
Twisted Prime
```

### PHP Program

Output:

```             Enter the prime number?
17
Twisted Prime
```
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